Harry joitces



H. JONES.

v BRAKE SHOE. APPLICATION FILED MAR. 8. I919.

Patented Aug. 19, 1919.

Invn tor,

fa ry Jana;

HARRY JoNRs, or em n, (NEW oRc nssIGNo 'ijo AMER CAN B AK snon FOUNDRY COMPANY, or MAI-IWAI-I, NEW JERSEY, ACORIBORATIQN or: NEW

JERSE Suffern, in the county of Rockland and State of New York, have invented an Improvement in 'BrakeShoes,- of which the I following description, in connectionwith the accompanying drawings, is a specification, like reference characters on'the drawings' representing like parts. i

This invention relates to brake shoes and c0nsists' 1nainly in a novel construction of an insert of hard material, embeddedfin the ni'aincasting of a brake shoe to increase the effectiveness and serviceability of the brake shoe. 1 'e s In Patent No. 1202529 granted October 24, 191 6, I have shown a brake shoeflprovided with an insert composed of a hard wear-resisting material in open-work form, havingincorporated in it a core ofductile material, and the present invention may be regarded as an improvement upon the construction forming the subject of that patent.

As shown in said patent the ductile core was embedded in a hard iron alloy and was incorporated in the insert by dipping' a suitably open-work formed of foraminous core into the hard material while'in molten condition, which resulted informing a coating of the hard material on the core.

Such'procedureis attended wi 11 some difficulties especially in making the larger sizes, which difficulties are avoided in the construction forming the subject of the present invention.

Furthermore the sectional shape of the insert when for1'1'1ed'bydippingis such that a ftcrthe brake shoe and insert have been reduced to a certain extent 'by wear, the portion of the insert that remains embedded in the softer material of the brake shoe is not interlocked therewith. andisliable to be dislodged or broken away,- leaving cavities in the face of thewbrak'e shoe, an effect which. is detrimental.

This is. owing to the fact that the adhesion between themetal of the" insert and the metal cast upon it is not very great,and 1 BRAKE-snort Specification tr Lettersratent.

Application filed March s, 1919." Serial no. 2311449."

the" material of the shoe"untilthefrnaterial of the insert is substantially entirely worn away.

The term dovetail will be used to designatethissec'tional formation oft'he insert,

it being intended that'the ternr shall be understood as. including any form in which the cross sectional shape of'the embedded portion of the insert increases in width as it ijncre'i'ases'ih depth erdistancefrom' working" face of the shoe, so that the material of" the shoe over-hangs and engax es positively witlr'the material of the insert until the latter is substantially entirely worn away;

Theinsert forming thesubject of the present invention having thegeneral foraminous or o en-work form and the dovetail sectional shape above-indicated,- is cast in a mold, the cavity 'ofwhi'ch contains the foraminous ductile core member, which thus becomes surrounded by and embedded in the casting made from the hard wear-resisting material, which casting istherea'fter incorporated in the brake shoe in the usual mane nerby l placing it in a suitable mold cavity and running in the cast iron of which the main portion of the brake shoe body is made."

-Figuref1 is" an elevation of the working face of a' brake shoe, provided withan insert, embodying this invention;

Fig; 2*isa s'i 'l'ar view of the insert as it appearsbefore being incorporated in the brake shoe, said insert being shown partly in sectionto' show the core'of ductile material;

ig. 3i'sa cross's'ectional view on lin e a Fig. .lgand Fig. 4, is a cross sectional view on line arfll i'gLQV k As shown in Fig. 1, the insert 2, is foraminous, or of open-work} formation, being composed of portions-that intersect preferably at the acute angle shown, the general formation being practically like that of what is now lmown' as expanded metah This specific form of the foraminous or open-work insert is not essential, although itis desirable because of its similarity to that of expanded metal, one or more pieces of which may be employed to constitute the ductile core 3 of the insert.

When expanded metal is used for the ductile core of the insert, one or more strips of the expanded metal are placed in the cavity of a suitable mold, and the molten material forming the main body of the insert is poured into the mold, the result being that the ductile core is incorporated inthe insert throughout the intersecting bars, or parts of which the open-work insert is made up.

The material of which the main body "or the insert is-"composed, may be any suitable" hard wear-resisting materlal, such as iron H alloys containing various proportions of carbon in solution, and, various other ingredients, making a ,metal such as is variously known in shop parlance as hard steel, or cruciblesteel, or white iron; or chilling cast iron, such iron alloys having been found satisfactory in practical service.

- Referring to the figures of the drawing which show the sectional shape of the in sert it will be seen that the insert is ofa general tapering form, being ofless thickness at the vwearing face 4 of the brake shoe than at thesurface which lies at the great 25 est depth-from said face in the body of the brake shoe; i 1 i I This tapering or dovetail formation .facilitates the drawing. of the pattern for the insert from the mold and also, causes the insert to interlock with the material of the main body of the brake shoe, theinterlocking or dovetail engagement of the insert in the body of the brake shoe remaining until the insert and material of the shoe at the sides ofthe insert are entirely worn away.

The open work formation of the insert has practically the same advantages as were pointed out for the sinuous insert shown in my prior Patent No. 995012, dated June 13, 1911,.and as that of the hard metal insert shown in my prior Patent No. 1202529, hereinbefore referred-to, but the cast or molded insert forming the subject of the present invention affords a better distribution of'the hard material in the body of the brakeshoe anda more effective interlocking of the ininserts in the cavity of the brake shoe mold,

and casting the remainder of the body portion 5 of the brake shoe around the same.

By having the intersecting bars or portions of the foraminous or open-work insert disposed diagonally int-he brake shoe body as represented it'will be seen that the wearving face of the shoe presents alternating "portions of the hard and soft material in "the line of frictional movement of the wheel tread along the face of the shoe, throughout the .width ofthesame, which is found to be effective for affording a high frictional coeflicient, and also for producing a more uniform wearing action upon the frictional surfaces than is the case when the hard and softer portions are less equally distributed throughout the wearing face of the shoe, and especially when the hard portion extends uninterrupted ,for a considerable distance inrthe direction of the movement of the wheel tread. 1

It is not essential that the core of ductile material should .be a unitary piece of expanded .metal,. although that is an exceptionally convenient construction for introducing-the strands of ductile core material into the mold in which the insert is cast. The core material may be merely laid in the cavity of the mold in which the insert is cast and will be more or less floated in the casting operation, so as to become completely surrounded and inclosed by the hard material of the insert as shown in the drawings. v,VVhile a single piece or strip of the core material is shown and has been found to be sufficient for the performance of its function in connectionwith the harder but more brittle material of the insert, there is no limitation to any definite number of lines or strands of the core material incorporated in the hard material of the insert.

. What I claim is: i

1. A brake shoe insert composed of a foraminous or open work casting of hard wear-resisting iron alloy having a core of ductile 'material incorporated and inclosed therein, said insert being of dbvetail sectional shape substantially as and for the purpose described.

2. A brake shoe comprising a cast metal body having embedded therein a cast metal insert, composed ofa foraminous castingof hard wear-resisting material of dovetail sectional-shape, having inclosed within it a core of ductile material.

In testimony whereof I have signed my name to this specification.

HARRY JONES.

v(lopies of this patent may be obtained or five cents eacJi,'-by addressing the Commissioner of latents,

. e vWashington, D. G. 

